The problem historically is that these increased options tend to go hand in hand with efforts to crappify the experience for those not paying extra in an attempt to "encourage" them to pay more. See "economy plus" ie. "Cram in more seats to shrink seat space except for a few that will stay the same that we can charge more for".

This is also a part of the game to avoid listing high fares on affiliate travel sites but then charging more through upcharges like this in an attempt to mask overall increases to average fare prices.